The U.S. House of Representatives has been frozen at 435 members for almost a century, and in that time the nation's population has grown by more than 200 percent. With the number of citizens represented by each House member now dramatically larger, is a major consequence of this historical disparity a diminished quality of representation? Brian Frederick uses empirical data to scrutinize whether representation has been undermined by keeping a ceiling on the number of seats available in the House. He examines the influence of constituency size on several metrics of representation--including estimating the effects on electoral competition, policy responsiveness, and citizen contact with and approval of their representatives--and argues that now is the time for the House to be increased in order to better represent a rapidly growing country.